The present invention relates generally to the field of computer resource virtualization, and more particularly to live partition migration between physical computing systems.
Computer systems typically include a combination of hardware and software components, application programs, operating systems, processors, buses, memory, input/output devices, etc. One area of advancement includes data centers providing cloud services with various types of virtualization services. Most computer virtualization systems and services create logical partitions (LPARs), also referred to as virtual machines (VM), on a computer system, such as, for example, a computer server. The virtual machine or logical partition (LPAR) is generally a software-based emulation of a physical computer. Most virtualization services make use of massive amounts of data input/output (I/O) traffic and network bandwidth. The massive amounts of data are usually stored in a network of storage devices that may be linked together and accessed through a storage area network (SAN). The storage area network (SAN) is divided into logical units identified by logical unit numbers (LUNs). The virtual machine or LPAR accesses necessary storage devices or LUNs using virtual ports which correspond to physical ports on the host computer server that are connected to the storage area network (SAN). Each virtual connection between the virtual machine or LPAR has a World Wide Port Name (WWPN). The virtual machine or LPAR uses the WWPN to access one or more LUNS via the storage area network (SAN).
Logical partition migration (LPM) allows a system administrator or other user to migrate a logical partition (LPAR), or virtual machine (VM), from one server computer (source server computer), or central electronics complex (CEC), to another server computer (destination server computer) or another CEC. The virtual machine (VM) or LPAR that is being moved in the LPM operation is known as the “mobile partition.” In such virtualized computing environments, logical partition mobility or migration (LPM), preferably live partition mobility, in which a logical partition (LPAR), or virtual machine (VM), executing on a first host computer server is migrated to a second host (target or destination) computer server, may be performed for a number of reasons, including to avoid outages for planned server maintenance, for load balancing across multiple servers, for energy conservation, and the like.